The Genetic Linkage and Epidemiology Core is responsible for the organizing the flow of scientific data and maintaining its integrity, and for carrying out the necessary analyses in statistical genetics, particularly genetic linkage analysis. It is expected that in most projects requiring use of this Core, disease genes will have to be localized on the human gene map. To this end, for a given disease project, family pedigrees will be collected by the corresponding project director, and marker genotypes will-be determined in the molecular genetics Core. Phenotype and genotype data for each individual then needs to be entered in a computer at the facilities of the Core and linkage analysis will be carried out with the ease of the LINKAGE programs.